@ Psychrates: Actually Underground Sea is the most expensive now. Tundra used to be the most sought after one back in the days of Revised. That made sense since white and blue were the slowest colors and generally more of their best cards required two specific color mana. With Dark Ritual going out of print and white picking up more cards to help with mana (Tithe, for example), it makes sense that Underground Sea is now the most valuable. Still, all original dual lands deserve 5 stars.

Now that would probably annoy some collectors even more than it is unlikely that Wizards would ever print this.Still, i think it would be cool as hell :D

(The original Dual Lands are on the Reserved List, but Wizards can still print them in special sets that don't make them legal in Standard again.)

Having them with top-notch artwork in the new frame, maybe even with a special textbox design (for example in a fashion of Basic Lands these days, like having two large halves of each accordant mana symbol next to each other) would certainly make more than just a few players wet their pants.

The best dual land? Black had mana accel back in the day so that leaves white and blue as the two weakest colors mana-wise. Of course if you run Tundra you're probably running white and white was pretty laughable back in the day.

Red and Green were the truly pitiful colors. While none of the Jund shard of the color pie could really operate very well, even the 3 color pairs its made up of were weak, because of how badly manacosted Creatures were back then, Black was at least better poised than Red or Green to fit some of its best cards into White-Blue-Artifacts Control. Which still dominates Vintage today, and hasn't changed as much as you'd think. This began to be fixed a bit in Legends (which saw in general lots of power for the whole Color Wheel get printed) and then by the end of Mirage Block we had something closer to a Stone Age... (see all)